MPs and peers have to ask themselves not only “what do the public want now?” but also “what will the public want then?”

Where will Brexit be in November 2018?

20 months on from the Article 50 notification, we should assume that the key terms of Brexit will be known. There will be loads of details to sort out later. But it should be clear what the essence of the deal is.

Michel Barnier the Commission’s chief negotiator has set a deadline of October 2018 for the terms to be agreed – that is to allow six months for ratification.

The European Parliament will have to agree the terms.

So will the Council of Ministers. That means that each member state will need to go through some sort of domestic process to determine its policy.

In the UK, Theresa May has promised Parliament a vote. However, her spokeswoman made clear that the UK will Leave the EU no matter how Parliament votes. So we should see that as the cynical gesture it is.

What the Public Want Now

The UK Polling Report round-up at the end of December 2016 found that people were still divided broadly half and half on whether Brexit would be a good thing. In other words, opinion has not moved since the referendum. That seems reasonable: nothing has changed in the real world. And I guess that most people have tuned out of the debate.

However, November 2016 polling by Yougov found that Remainers are split roughly 50:50 between those who thought that Brexit should be stopped for example by a second referendum and those who thought that the June result meant that Brexit must go ahead.

The Guardian/ ICM poll of 23 January 2017 shows that support for a rethink is growing. By now 38% of those polled want some form of decision on the terms with the option to Remain. The number of acquiescent Remainers is falling.

We should recognise that MPs voting for Article 50 to be invoked would be in line with not only the referendum result but also about two thirds of public opinion.

What will the Public want in November 2018?

Once the terms of Brexit are known, everything will be different.

First, the principles of good project management, of good government: no-one takes a project from idea to implementation without a project review. That project review of course includes the option to cancel the project.

So there should be a referendum on the terms of Brexit with the option to Remain.

That would be quite different from the June 2016 vote, when Leave had no plan and so every Leave voter could decide for themselves what Brexit meant. In 2018 there will be only one Brexit on the table – Theresa May’s hard Brexit.

Second, what will the public want then? No-one knows, of course, but here are some safe forecasts

* some of those who voted Leave will not like the deal that is actually on offer, and many will not like the price tag attached. They will prefer to Remain.

* some of the Remainers who currently think that they must go along with Brexit because of the June vote will think that actually they should try to stop it. All that ratification activity going on in Europe and the terms of Theresa May’s hard Brexit will lead people to focus again on the question. They will then remember why they prefer EU membership.

So it is likely that the slim majority in June 2016 for Brexit – the Brexit of each elector’s choice – will disappear in the harsh light of Theresa May’s Brexit. And the acquiescence of the pro-EU public in going ahead with Brexit is also likely to be much reduced.

A parliamentary vote will not resolve the crisis we will then face. It would be like deciding a battle by single combat. The losing side would not feel that they had had a full chance to make their case. And it would place an intolerable burden on MPs, given the divisions in the country.

What MPs and Peers should do now

MPs and peers should amend the Government’s Article 50 Bill to provide for a referendum on the terms with the option to Remain.

That proposal now has the support of a quarter of the electorate, and we can be sure it will be more popular in November 2018. But then it may be too late to set up the referendum against the wishes of the Government.

MPs can justify the referendum to all their constituents – both Leavers and Remainers:

* a vote for Article 50 honours the June referendum result;

* good government calls for a review of the project once there is a plan;

* a referendum on the terms hands back to the electorate the next decision in the process. It allows voters to Take back Control.

What you can do

Write to your MP, to the Labour Party and SNP leadership, to any peer you know. Ask them to support the amendment to the Article 50 Bill that will provide for a referendum on the terms with the option to Remain.

Michael Romberg is a retired senior civil servant and a member of the European Movement. You can read more from Michael on his Facebook page: Campaign for the Real Referendum – on the Terms of Brexit. It has model letters to MPs, if you would like some inspiration.

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